<template>
  <section class="msite">
    <!--首页头部-->
    <HeaderTop :title="address.name">
      <router-link to="/search" class="header_search" slot="left">
        <i class="iconfont icon-sousuo"></i>
      </router-link>
      <router-link :to="userInfo._id ? '/userinfo' : '/login'" class="header_login" slot="right">
        <span class="header_login_text" v-if="!userInfo._id">登录|注册</span>
        <span class="header_login_text" v-else>
          <i class="iconfont icon-person"></i>
        </span>
      </router-link>
    </HeaderTop>
    <!--首页导航-->
    <nav class="msite_nav">
      <div class="swiper-container" v-if="categorys.length > 0">
        <div class="swiper-wrapper">
          <div class="swiper-slide" v-for="(categorys, index) in categorysArr" :key="index">
            <a href="javascript:;" class="link_to_food"  v-for="(category, index) in categorys" :key="index">
              <div class="food_container">
                <img :src=" baseImageUrl + category.image_url">
              </div>
              <span>{{category.title}}</span>
            </a>
          </div>
        </div>
        <!-- Add Pagination -->
        <div class="swiper-pagination"></div>
      </div>
      <img src="./images/msite_back.svg" alt="back" v-else>
    </nav>
    <!--首页附近商家-->
    <div class="msite_shop_list">
      <div class="shop_header">
        <i class="iconfont icon-xuanxiang"></i>
        <span class="shop_header_title">附近商家</span>
      </div>
      <ShopList></ShopList>
    </div>
  </section>
</template>

<script>
  import HeaderTop from '../../components/HeaderTop/HeaderTop'
  import ShopList from '../../components/ShopList/ShopList'
  import Swiper from 'swiper'
  import 'swiper/css/swiper.min.css'
  import {mapState} from 'vuex'
  export default {
    name: '',
    data () {
      return {
        baseImageUrl: 'https://fuss10.elemecdn.com',
      }
    },
    components: {
      HeaderTop,
      Swiper,
      ShopList
    },
    computed: {
      ...mapState(['address', 'categorys', 'userInfo']),
      // 根据categorys一维数组，生成一个二维数组
      categorysArr () {
        const {categorys} = this;
        // 准备空的2二维数组
        const arr = [];
        let minArr= [];
        categorys.forEach(c => {
          // 如果当前小数组已经满了创建一个新的小数组
          if(minArr.length === 8){
            minArr = [];
          }
          // 如果小数组minArr是空的，将小数组保存到大数组中
          if(minArr.length === 0){
            arr.push(minArr);
          }
          minArr.push(c);
        })
        console.log(arr)
        return arr;
      },
    },
    mounted () {
      this.$store.dispatch('getCategorys');
      this.$store.dispatch('getShops');
    },
    methods: {

    },
    watch: {
      categorys (value) { // categorys数组中有数据了，在异步更新界面之前执行
        // 使用setTimeout可以实现效果，但是不是太好
        // setTimeout(() => {
        //   // 创建一个Swiper实例对象，实现轮播
        //   /* eslint-disable no-new */
        //   new Swiper('.swiper-container', {
        //     loop: true, // 可以循环轮播
        //     pagination: {
        //       el: '.swiper-pagination'
        //     }
        //   });
        // }, 100);
        // 界面更新就立即穿件swiper对象
        this.$nextTick(() => { // 一旦完成界面更新，立即调用（此条语句要写在数据更新以后）
          // 创建一个Swiper实例对象，实现轮播
          /* eslint-disable no-new */
          new Swiper('.swiper-container', {
            loop: true, // 可以循环轮播
            pagination: {
              el: '.swiper-pagination'
            }
          });
        })
      },
    },
  }
</script>

<style scoped lang='stylus' ref='stylesheet/stylus'>
  @import '../../common/stylus/mixins.styl'
  .msite //首页
    width 100%

    .msite_nav
      bottom-border-1px(#e4e4e4)
      margin-top 45px
      height 200px
      background #fff

      .swiper-container
        width 100%
        height 100%

        .swiper-wrapper
          width 100%
          height 100%

          .swiper-slide
            display flex
            justify-content center
            align-items flex-start
            flex-wrap wrap

            .link_to_food
              width 25%

              .food_container
                display block
                width 100%
                text-align center
                padding-bottom 10px
                font-size 0

                img
                  display inline-block
                  width 50px
                  height 50px

              span
                display block
                width 100%
                text-align center
                font-size 13px
                color #666

        .swiper-pagination
          > span.swiper-pagination-bullet-active
            background #66ccff

    .msite_shop_list
      top-border-1px(#e4e4e4)
      margin-top 10px
      background #fff

      .shop_header
        padding 10px 10px 0

        .shop_icon
          margin-left 5px
          color #999

        .shop_header_title
          color #999
          font-size 14px
          line-height 20px
</style>
